On closer inspection, tennis28 actually mentions their last update date for their rankings tables here: http://www.tennis28.com/rankings/index.html (Feb 14 as of now) So, assuming this site uses a script on the complete, perfect, database of the rankings (since July 1984 as they mention), we can simply use their data and add the last 4 weeks ourselves. Except for consecutive streaks in top 2 and 3, and the Lendl & Connors stats.
(I verified their update date: they have Nadal at 83 weeks at #1 as of feb 14, which is correct; he will have 87 weeks next Monday Mar 14.)

BTW Sampras does not have more than 3.5 yrs consecutive top 2, he was #3 for 1 week or so early 1996 (according to tennis28 graph)
Federer's total and consecutive top 3 counts are equal. Once he entered the top 3 on July 7 2003, he has never left it.
Reaching Lendl in total top 2 will be a challenge for Federer, he needs to keep off Djokovic for a while. Total top 3 may be easier.